Steam-boiler



(NQ'Moael.)

W. A. HBNNESSEY.

I Steam Boiler.n No. 242,314. Patented May 31, |881.

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m'llllll 'lllllll'l IN VENTOR WITNESSES h By hw' .Attorneys NITED STATES PATENT Fluoa WTILLIAM A. HENNESSEY, OF SPRINGFIELD, MASSACHUSETTS.

STEAM-BOILER.

SPECIFICATION forming part of Letters Patent No. 242,314, dated May 31, 1881.

' Application filed January 27, 1881. (No model.) l

To. all whom it may concern:

Be it known that I, WILLIAM A. HENNEssEY, of Springfield, in the county of Hampden and State of Massachusetts, have invented certain new and useful Improvements in Steam- Boilers; and I do hereby declare that the following is a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accom panying drawings, which form a part of this specification.

Figure l is a longitudinal vertical sectional view, and Fig. 2 is a vertical cross-section, of my improved boiler, and Fig. 3 is a horizontal sectional view.

Similar letters of reference indicate corresponding parts in all the iigures.

This invention relates to steam-boilers; and it consists in certain improvements in the construction of the same, which will be hereinafter described, and particularly pointed out in the claim.

It is well known that in tubular boilers as at present constructed the iame and gases of combustion pass directly through the centrally-located tubes or lines, causing' them to wear out in much less time than the outerones, and correspondingly decreasing the efficiency of the boiler.

My invention has for its object to so construct the boiler as to equalize the draft through the iues to the greatest possible extent, thereby increasing the usefulness of the boiler and economizin g fuel.

The construction of my improved boiler will be readily understood by reference to the accompanyin g drawings, in which- A represents the cylindrical shell of the boiler, riveted to which is an auxiliary cylinder, B, projecting at the rear end, as shown at C. Of the lines or tubes about one-half of the en tire number are located in the auxiliary shell B, as represented by the letters D D. The remainder, E, of the lines are located in the main shell A, as shown. The front end of the boiler is formed with a chamber, F, as shown.

B y reference to the drawings hereto annexed the operation and advantages ot' my invention will be readily understood. 5o

The llame, gases, and products ot'combnstion pass from the furnace under the boiler, back, as indicated by the' arrow, through the outer tlues, E, to the chamber F, from whence they pass through the fines D in shell B out to the chimney-lines.

It will be seen that the llames, Src., pass directly under and around the projecting end C of the center llues, the advantage of which will be readily seen, heat which is usually wasted 6o being in this manner utilized.

I prefer in practice to make the boiler with such an arrangement of dampers that immediately on starting up the lire the draft may be sent under the boiler or through the outer tubes only, and from thence directly u p through the chimney.

Having thus described my invention, I claim and desire to secure by Letters Patent of the United States- 7o In a Hue and tubular steam-boiler, the combination of the outer cylinder, A, and inner cylinder, B, having its rear end projecting from said cylinder A, each cylinder being provided with re-tubes and return smoke-chambers, all constructed and arranged to cause the products ot' combustion to first impingefon their outer surface and then through the tubes on their innersurface, as shown and described.

In testimony that I claim the foregoing as 8o my own I have hereto affixed my signature in presence of two Witnesses.

VILLIAM A. HENNESSEY.

Witnesses:

J As. F. ONEIL, HARRY WILLIAMs. 

